Efficient Er3+ doped single-component Cs2Ag(Na)In(Bi)Cl6 phosphors for full-spectrum light-emitting diodes

Single-component phosphors with efficient and stable white-light emission are designed to overcome the trouble of various deteriorations and reabsorptions in the conventional mixing multiple-component phosphors for lighting applications. Here, Er3+ is introduced partially into the double perovskite Cs2Ag(Na)In(Bi)Cl6 lattice to tune white-light emission through adjusting its content. The as-synthesized material itself possesses strong tunable white-light emission under irradiation by 405 nm light due to the combination of self-trapped excitons emission and efficient characteristic emission of Er3+. Steady-state photoluminescence (PL) and time-resolved PL spectra are measured to characterize luminescence properties and clarify the luminescence mechanism. The PL quantum yield of undoped Cs2Ag(Na)In(Bi)Cl6 can achieve 64%. After doping 2 mmol Er3+, energy transfer efficiency from perovskite to Er3+ can reach 30.1%, with an improved PL quantum yield of 71%. The full-spectrum white-light emission can be realized by the Er3+ doped Cs2Ag(Na)In(Bi)Cl6 phosphors-converted 410–420 nm light-emitting diode. Commission International de I'Eclairage (CIE) color coordinates of white light can be improved from (0.47, 0.41) to (0.33, 0.35) with the increase of Er3+ content, and the corresponding color temperature is tuned from 2532 to 5760 K. These characteristics demonstrate that Er3+ doped Cs2Ag(Na)In(Bi)Cl6 phosphors are promising single-component white-light phosphors for next-generation lighting.